What to eat and what to skip when you’re pregnant

I have a master’s degree in nutrition. I’ve spent the last dozen years as a health writer, interviewing experts and then telling women how to eat healthfully in all sorts of scenarios: when they want to lose weight, when they’re training for a marathon, when they’re looking to lower their cholesterol or boost their bone density and, yes, when they’re expecting.

But it wasn’t until I got pregnant with my first son three and half years ago that I fully realized that eating during pregnancy can feel complicated. Confusing. Yes, you need plenty of protein, calcium, iron and folate. You should be faithfully taking that prenatal vitamin. But what about fish? You’re supposed to be filling up with omega-3s, but there’s all that business about mercury, which can harm your baby’s brain. Is coffee legal? Why can’t you have cold cuts? Now, having been through two pregnancies, I feel like I can dole out the advice with better perspective. Read on for answers to some of these puzzling eating-while-preggo issues. (Of course, I am not a medical doctor, and you should always check in with your health-care provider!)

Can I have a drink? If you’re even considering it, this is definitely a question to discuss with your doctor. Sure, maybe you know someone who lived in France and had a glass of wine every night during her pregnancy and her baby is brilliant. Or you caught wind of the British study published in Journal of Epidemiology and Community Health last year that suggested a drink or two a week during pregnancy might be ok. Fact is, experts still advise avoiding alcohol completely during pregnancy. Alcohol easily crosses the placenta to your baby, whose liver is not well enough developed to break it down. Drinking alcohol can cause your baby to be too small—and may increase the risk of preterm delivery and miscarriage. It may also affect your baby’s heart and brain. I didn’t drink at all during my pregnancies. (Nonetheless, judging women who sip some wine during theirs isn’t my business.) Like I said, talk to your doctor.

What’s the deal with fish? Fish offers protein (which you need a little more of when you’re pregnant); plus, fatty types like salmon, tuna and sardines also provide omega-3 fats that are good for a baby’s brain. Since some seafood contains mercury, a toxin that may harm a baby’s brain, the Food and Drug Administration (along with the Environmental Protection Agency) recommends that pregnant women avoid eating shark, swordfish, king mackerel and tilefish, large fish that tend to accumulate high levels of mercury. They also tell pregnant women to limit total fish intake to 12 ounces per week, with no more than 6 ounces coming from albacore (white) tuna, which is moderately high in mercury. Two great low-in-mercury, high-in-DHA catches: salmon and sardines.

Why can’t I have cold cuts? Short answer: Listeria monocytogenes, a bacteria most often found in deli meats and unpasteurized dairy products. One third of the 2,500 people affected by listeriosis (the illness caused by these bacteria) each year are pregnant women. (Chalk it up to a suppressed immune system.) Initial symptoms—fever, chills, muscle aches and back pain—don’t seem serious, but one in five cases of listeriosis is fatal. What’s more, this disease can spread to the fetus, leading to preterm delivery, miscarriage or a stillbirth. So that’s why you shouldn’t have deli meats or any other food that’s likely to be contaminated by the bacteria, including unpasteurized milk (and juices) and cheeses made from “raw” (unpasteurized) milk. Dying for a deli sandwich? Heat it until it’s steaming hot and then it’s safe. Same goes for bacon and hot dogs, but I seriously don’t understand why you’d be eating those raw.

Do I need to eat everything organic? Babies’ developing brains are more susceptible to the harmful effects of pesticides than adults so it’s a good idea to go organic when you can. Since organic fruits and vegetables can be pricy, I prioritize my buying with the Environmental Working Group’s Dirty Dozen list, which outlines the veggies and fruits containing the highest pesticide residues. Find out all 12 foods you should considering buying organic.

What about that cup of coffee? The problem with coffee while pregnant is the caffeine: it can cross the placenta and affect fetal heart rate and breathing. (Some studies also link coffee intake with low birthrate and higher rates of miscarriage, but this research is controversial.) Experts advise that during pregnancy you limit caffeine intake to about 300 mg a day, which generally equates to two to three cups of coffee. (Remember, a “cup” is 8 ounces, not the size of the mug you’re drinking from.) A cup of tea contains about 40 mg of caffeine; one ounce of dark chocolate has 20 mg. Personally, when I was pregnant, I had a “fully charged” cup of joe each morning and a cup of decaf each afternoon. On weekends, I made decaf lattes at home for a yummy dose of dairy—something I didn’t always take the time to do before I was pregnant.

Which brings me to my last point: when it comes to your diet during pregnancy, try to embrace the changes you need to make. Think: they’re not only keeping your baby safe, but may be helping you to jump-start a healthier way of eating that’ll stick around long after the baby’s born.